Hephzibah Menuhin had a musical gift most people only dream of. Her refusal to be defined by it led her to reinvent herself not once, but twice in her remarkable life.

Born in 1920 in San Francisco she was, like her world-renowned brother Yehudi, a child prodigy, simultaneously thrown into the spotlight at an early age and closeted by a dominating, controlling mother.

In the brief spring between the world wars, the Menuhin family travelled extensively, driven by the demands of Yehudi's career. Then Hephzibah, aged seventeen, celebrated as her brother's musical partner and on the brink of greatness in her own right, turned her back on performing. She married Lindsay Nicholas, the Melbourne-born heir to a pharmaceutical fortune, and moved to his sheep property in western Victoria.

Far from playing the conventional wife of a wealthy grazier, Hephzibah threw herself into humanitarian projects in her adopted country. She raised two sons and eventually resumed performing, both solo and with Yehudi, to international acclaim. But after sixteen years that seemed from the outside happy and fulfilled, she met a man who drew her to question what she thought she knew - and to abandon her established life a second time.

What makes a woman walk out on her children? What makes her turn her back on a brilliant artistic career? An Exacting Heart reveals the complex and contradictory nature of Hephzibah Menuhin: warm-hearted, humorous, astute, generous, occasionally ruthless and wrong-headed. In portraying the life and times of this fascinating and mercurial woman. Jacqueline Kent examines not only the consequences of possessing great talent, but the costs and rewards of gambling for high emotional stakes.